My wife found this idea online. Some shaving cream mixed with food coloring. Hours of fun for my 4 year old daughter. Of course sometimes she needs to shower off after her bath, but she gets to paint on herself and the walls

Great expression on her face, and nice and sharp. I like your aperture choice, just enough detail to tell us where you are, and to see the tools of the artist. This looks like a lot of fun. I will have to remember that one for when my daughter gets older.